Projection engineering (Jan 1932-Mar 1933)

10 PROJECTION ENGINEERING Sound and light projection in the United States Navy By Daniel Buckley* Officers and enlisted men in Navy service make practical use of modern projection equipment. Films employed for instructional purposes and for entertainment. PRIMARILY the U. S. Navy motion picture service is provided for the recreation of enlisted men. It is classed by the producers as "non-theatrical." Considering the number of men in this military organization and the temperamental characteristics of the individual something must be done to break up the monotony of daily routine aboard a "man-of-war." A "man-of-warsman" is on duty twentyfour hours every day, in each week, month, year, and enlistment period, regardless of whether he happens to be ashore, on liberty or aboard ship. In order to break up this monotonous routine while aboardship there must be recreation, in the form of education and entertainment. Motion picture projection accomplishes a great deal toward relieving the tension and the requirement, that a "man-of-warsman" answer a call to quarters at a moment's notice. When sight alone was used for conveying a projected image from the screen to the person in the audience many different conceptions were formed while viewing the projected scenes. With the advent of sound in the motion picture field only one thought at a time can be transmitted to the audience and that the correct one. Every one attending the performance receives the same impression because of the scene projected and the sound accompanying it. No opportunity is left for the individual to exercise imagination. This proves the advantage of the sound motion picture in contrast to the silent especially where educational films are concerned, where the same thought must be conveyed to all persons attending the exhibition. In the navy we are taking the opportunity of showing educational films which improve the ability of the sailor with his required duty and aid him toward attaining a higher *C. E M. U. S. Navy {Instructor). battle efficiency rating for the ship upon which he is serving. These films are shown usually at times during the day to prevent interference with the regular performance each evening given the crews for entertainment purposes. During the entertainment performances a well-balanced program is given which may consist of a news reel, comedy, and feature picture. In the navy there are men holding special professional ratings such as radiomen and electricians' mates. Due to the necessity of using (amplifiers in sound motion pictures, it seemed that the most logical profession to take up this study would be the radio man. Such was the case in the civilian field, but foresight used by the navy department allotted this study to the electrician's mates, which has proven beneficial to the service. The radio man has to confine his activities to communications, qualifying himself in procedure and operating his set as specified by the Bureau of Engineering instructions. That field alone for the radioman covers quite a range in naval operations. The electricians' mates, however, have now introduced in their work various other equipments and instruments using vacuum tube amplifiers, in addition to motion picture equipment, which do not pertain to communications. Since vacuum tube amplifiers are being introduced into various electrical systems, naturally the most logical workers to take up the study of sound motion pictures are the electricians' mates. It is the men following the electrical profession in the navy to whom instructions are given at the navy sound motion picture technicians' schools. A school is being maintained at the navy yard, Brooklyn, N. Y., for men located aboard ships and stations doing duty in the vicinity of the east coast. Another school is maintained at the naval training station, San Diego, California, to accommodate the men of the west coast doing duty aboard ships and stations there, including men from the Hawaiian Islands and Guam. A temporary school is located at Cavite, Philippine Islands, for the men doing duty in the vicinity of Asiatic countries. Proficiency Required Not only is it necessary for the man operating a sound motion picture equipment to be qualified in maintaining amplifiers, projectors and sound attachments, at a high standard of efficiency at all times, but he must also be proficient in the projection of pictures. He is taught in the navy schools all the requirements in the projection of a good picture and as far as his equipment is concerned to reproduce the sound as faithfully as possible with the apparatus at his command. A great deal depends upon the sound film. He is taught to preserve the film in order to obtain its maximum efficiency as regards definition of picture and sound track. To maintain the film (care and handling) so as to obtain as great a length of life as possible during its rounds of travel from one ship to another. The films on some ships may be shown as many as three times during a night. One performance may be given to the crew in general, then a performance for the chief petty officers and again may be exhibited to the commissioned officers; setting up portable equipments, exhibiting to the two latter classes of men, in their quarters. The subjects necessary for students at the schools to comprehend are : The physics of sound, light, lenses, acoustics, and mathematical problems pertaining to acoustical conditions of certain enclosures. The electron theory is gone into as far as necessary to understand intelligently the operation of that magic bottle of electricity known as the vacuum tube. Also the physical construction of a vacuum tube, during the process of manufacture, the principles and properties of vacuum tubes and the accompanying amplifier, including photoelectric effects, and photoelectric cells, as used in sound motion picture work. The Simplex projector (standard theater type) is studied thoroughly, then each man individually disassembles and assembles the projector head and makes all proper adjustments to parts in contact with the film proper. This being part of the student's practical work during the course. The R. C. A. Photophone sound attachment likewise undergoes the same process of dissection as the projector head. Loudspeakers of the dynamic cone type are disassembled, and each man required to know how to make the required adjustments of the individual parts of the speakers to eliminate defects due to "buzz," and matter